Optical Design For Multimirror Telescope System

The reflective telescopes are widely used in the field of remote sensing. This dissertation shows the summary of the applications and the optical design methods about lots of reflective telescopes.The reflective telescope design method has achived four-mirror telescope at present. With the guidance of the method, the four-mirror telescope can be designed efficiently. The five-mirror telescope has been manufactured by Raytheon Company in2011, but the method for the five-mirror telescope has not been built, then the development of the design method is slower than the application of the telescope. In order to change the condition between the method and the application, the optical design methods for coaxial five-mirror telescope and coaxial six-mirror telescope were built respectively in this dissertation with the help of the former results about optical designs while the first mirror was the entrance pupil.The optical design methods for coaxial five-mirror telescope, four-mirror telescope, three-mirror telescope, two-mirror telescope and one-mirror telescope can be deduced from the optical design method for coaxial six-mirror telescope. The optical design method for four-mirror telescope can be deduced from the methods for five-mirror telescope or six-mirror telescope. That is to say, the design method for more-mirror telescope includes the design method for fewer-mirror telescope, and the design method for fewer-mirror telescope is just a special example from the more-mirror telescope.In order to show how the optical design method guides the optical engineers to design reflective telescopes efficiently, two examples about two-mirror telescope and three-mirror telescope were shown in the dissertation. With the guidance of the optical design methods for reflective telescopes, the wide field of view off-axis three-mirror-anastigmatic telescope, the wide field of view off-axis four-mirror-anastigmatic telescope, the wide field of view off-axis five-mirror-anastigmatic telescope, and the wide field of view off-axis six-mirror-anastigmatic telescope were designed in this dissertation: 1. Three-mirror telescopeIt is difficult to design more than three channels in the off-axis three-mirror-anastigmatic telescope in the condition of wide field of view and fast F/#(such as F/3). It is also difficult to design the wide field of view off-axis three-mirror-anastigmatic telescope with an intermediate image without the guidance of the optical design method. A four-channel off-axis three-mirror-anastigmatic telescope was designed with the requirements of wide field of view (4.4°×0.2°), fast F/#(F/3). There is an intermediate image in the telescope. And three free-form-surface beam splitters were used.2. Four-mirror telescopeWith the guidance of four-mirror telescope optical design method, a compact off-axis four-mirror-anastigmatic telescope was designed with the requirements of wide field of view (16°×0.2°), fast F/#(F/3) and middle infrared wave band; a compact off-axis four-mirror-anastigmatic telescope was designed with the requirements of wide field of view (20°×1°), slow F/#(F/10) and visual wave band (including ultraviolet wave band).3. Five-mirror telescopeWith the guidance of five-mirror telescope optical design method, an off-axis five-mirror-anastigmatic telescope with four mirrors was designed with the requirements of wide field of view (20°×0.2°), fast F/#(F/3) and near infrared wave band.4. Six-mirror telescopeWith the guidance of six-mirror telescope optical design method, an off-axis six-mirror-anastigmatic telescope was designed with the requirements of wide field of view (32°×2°), fast F/#(F/3.33) and visual wave band (including ultraviolet wave band, near infrared wave band and short infrared wave band).The optical design methods for the coaxial five-mirror and coaxial six-mirror reflective telescopes could guide the optical engineers to design at present and in the future for a few years.